Interfacial Bonding and Chemical Stability of Hybrid Ceramic-Reinforced AA6061 Surface Composites Prepared by Friction Stir Processing

Aluminium matrix composites (AMCs) were produced using friction stir processing (FSP).The matrix material was aluminium alloy AA6061.As reinforcement particles, various kinds of ceramic particles have been used including Cu2O, Cr3C2, and BN.AA 6061 surface composites of 50% Cu2O -50% Cr3C2, 50% Cr3C2 -50% BN and 50% BN -50% Cu2O were effectively produced.Optical microscopy and field emission scanning electron microscopy were used to examine the microstructure.Results showed that the microstructure, hardness, impact strength, and wear test were not significantly affected by the kind of ceramic particle.Regardless of the location, every kind of ceramic particle produced a uniform dispersion and strong interfacial bonding in the stir zone.Nevertheless, AA6061AMC exhibited superior hardness and wear resistance compared to other AMCs produced in this work under the same set of experimental conditions.The observed microstructure is associated with the strengthening mechanisms and the change in the characteristics.The details of fracture mode are further presented.